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United States Patent | 5,012,683 |
Davis | May 7, 1991 |
A capacitive sensor is described having an element which traverses the outside of a container of liquid to ascertain the vertical locations of liquid interfaces in the container. The sensor uses an oscillator whose amplitude or phase is a function of the capacitance of the element.
Inventors: | Davis; James E. (Wilmington, DE) |
Assignee: | E. I. DuPont de Nemours and Company (Wilmington, DE) |
Appl. No.: | 466938 |
Filed: | January 18, 1990 |
Current U.S. Class: | 73/864.24; 73/290R |
Intern'l Class: | B01L 003/02 |
Field of Search: | 73/863.01,864.23,864.24,864.25,304 C,290 R 361/284 422/63,67,100 324/672,674,679,681,683 |
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Foreign Patent Documents | |||
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